Field of the Disclosure
The present disclosure relates to a display device, and more particularly, to an organic light emitting display device and a controller included in the organic light emitting display device.
Description of the Background
Recently, an organic light emitting display device is coming into the spotlight as a display device which has advantages, such as a fast response rate, a high contrast ratio, a high light emitting efficiency, a high luminance, and a wide viewing angle, by using an organic light emitting diode (OLED) which emits light by itself.
Such an organic light emitting display device displays an image by arranging organic light emitting diodes (OLEDs) and subpixels including a driving transistor, which drives the organic light emitting diodes, in a matrix form, and controlling brightness of a subpixel selected by a scan signal, according to gradation of data.
Circuit elements, such as the organic light emitting diodes (OLEDs) and the driving transistor, are degraded as a driving time passes.
As deterioration of the organic light emitting diodes (OLEDs) or the driving transistor included in the subpixel progresses, a unique characteristic value of each circuit element, such as a threshold voltage, a mobility, etc., becomes changed.
Due to a change in a unique characteristic value of each circuit element, a subpixel including a corresponding circuit element cannot accurately express brightness according to gradation of data, and this causes an overall image abnormality of an image displayed through an organic light emitting display panel.
Therefore, a technique of sensing characteristic values of circuit elements included in such subpixels and performing compensation of such changes according to a sensing result has been developed and applied.
However, there can occur an error in a procedure of measuring or transmitting sensing data for unique characteristic values of circuit elements, and such an error prevents accurate sensing and compensation, and thus results in a problem of generating defects in sensing and compensation.